Sampling of fluids within a well bore is becoming increasingly important as evaluation and development of a reservoir depends on the properties of the fluid in the reservoir. Downhole samples of the fluid are preferred to samples taken at the surface as they better represent downhole fluid properties. Fluid samples taken at the surface can have significantly different properties to a downhole sample due to variations in temperature and pressure that occur as the fluid travels to the surface and at the surface. Existing tools for downhole fluid sampling include a wireline conveyed sampling bottle which acquires a single sample downhole and is retrieved from downhole to surface. Wireline (coil tubing run) tools which are capable of pumping fluids from a borehole and from a reservoir formation into sampling chambers can also be used.
Once samples have been taken and placed within a sample bottle, the subsequent transport of the sample to a laboratory can cause irreversible changes in the sample which will alter its properties, and limit its usefulness in assessing actual downhole properties of the reservoir fluid. For example, often the sample is transferred from a sample bottle to another suitable container for transport. Variations in conditions surrounding the container during transport will affect the sample and its properties. Also the sample must be transferred out of the container once the laboratory is reached and again this can affect the sample.